A phase III randomized, controlled study to assess and compare the immunogenicity and tolerability of single and multi-dose vials of DTwP-Hib, a fully liquid quadravalent vaccine and their comparison with TETRAct-Hib vaccine in Indian infants aged 6-14 weeks

Both WHO and IAP encourage using combination vaccines, wherever feasible. The phase III trial reported here was conducted to assess and compare the immunogenicity, tolerability and safety of two quadravalent vaccines, Quadrovax^® (new vaccine), and TETRAct-Hib^® (available in the market) in a multicentre study, in India. In all, 361 infants aged 6-8 weeks were enrolled, out of which 339 completed the study. The vaccination was done at 6-10-14 weeks following EPI/WHO recommended immunization schedule. Blood samples were collected prior to the administration of first dose and one month after the third dose. Postvaccination, geometric mean titres for each component did not differ significantly between the single dose vial and multi dose vial subgroups and among the two study groups. Adverse events observed were within the range quoted in literature. Quadrovax^® vaccine manufactured by SIIL was found to be safe, immunogenic and non-inferior to the comparator vaccine. The quadravalent vaccine is best recommended in the second year of life when children receive their booster dose at 15-18 months. It can be given to infants during primary immunization series at 6, 10 and 14 weeks of age when Hepatitis B vaccine is given in a separate arm or to infants at 10 weeks who receive the Hepatitis B vaccine separately following the 0, 6 and 14 weeks or 0, 1 and 6 months schedule.     

Investigation on sodium valproate induced germ cell damage, oxidative stress and genotoxicity in male Swiss mice

Sodium valproate (VPA) is the most widely used antiepileptic drug for the treatment of epilepsy, bipolar psychiatric disorders and migraine. However, long-term VPA treatment has several adverse effects on the reproductive system. The present study was aimed to investigate the possible germ cell toxicity of VPA in mice. Animals were treated with VPA intraperitoneally for 10 and 28 days at the doses of 500 mg/kg-d and 100, 200 and 400 mg/kg-d, respectively, and were sacrificed 24h after the last dose. The germ cell toxicity of VPA was assessed using oxidative stress parameters, sperm count, sperm head morphology, sperm comet assay, 8-oxo-dG expression and histology. VPA treatment significantly decreased the sperm count, testes and epididymis weight and significantly increased the sperm head abnormality, sperm DNA damage, oxidative stress and 8-oxo-dG expression in the testes of mice. The present study illustrates that VPA induced germ cell toxicity in mice.     

Cytokine receptor CXCR4 mediates estrogen-independent tumorigenesis, metastasis, and resistance to endocrine therapy in human breast cancer

Estrogen independence and progression to a metastatic phenotype are hallmarks of therapeutic resistance and mortality in breast cancer patients. Metastasis has been associated with chemokine signaling through the SDF-1-CXCR4 axis. Thus, the development of estrogen independence and endocrine therapy resistance in breast cancer patients may be driven by SDF-1-CXCR4 signaling. Here we report that CXCR4 overexpression is indeed correlated with worse prognosis and decreased patient survival irrespective of the status of the estrogen receptor (ER). Constitutive activation of CXCR4 in poorly metastatic MCF-7 cells led to enhanced tumor growth and metastases that could be reversed by CXCR4 inhibition. CXCR4 overexpression in MCF-7 cells promoted estrogen independence in vivo, whereas exogenous SDF-1 treatment negated the inhibitory effects of treatment with the anti-estrogen ICI 182,780 on CXCR4-mediated tumor growth. The effects of CXCR4 overexpression were correlated with SDF-1-mediated activation of downstream signaling via ERK1/2 and p38 MAPK (mitogen activated protein kinase) and with an enhancement of ER-mediated gene expression. Together, these results show that enhanced CXCR4 signaling is sufficient to drive ER-positive breast cancers to a metastatic and endocrine therapy-resistant phenotype via increased MAPK signaling. Our findings highlight CXCR4 signaling as a rational therapeutic target for the treatment of ER-positive, estrogen-independent breast carcinomas needing improved clinical management.     

CRAC channels and Ca2+ signaling in mast cells

Summary:  Mast cells are integral members of the immune system. Upon activation by a rise in cytoplasmic Ca²⁺, they release a battery of paracrine signals, chemokines, and cytokines, which help sculpt the subsequent immune response. Ca²⁺ entry through store-operated Ca²⁺ release-activated Ca²⁺ (CRAC) channels in the plasma membrane is central for driving most of these responses. The molecular basis of the CRAC channel has been identified, with Orai1 forming the channel pore. Recent work has revealed that a range of mast cell responses are activated by spatially restricted Ca²⁺ signals just below the plasma membrane. These Ca²⁺ microdomains can activate cytosolic enzymes, leading to the generation of intracellular messengers as well as proinflammatory molecules like LTC₄. In this review, we describe key features of CRAC channels in mast cells, how they generate local Ca²⁺ signals, and how the cell can decode these restricted signals to generate a raft of responses.     

Controlled delivery of antimicrobial gallium ions from phosphate-based glasses

Gallium-doped phosphate-based glasses (PBGs) have been recently shown to have antibacterial activity. However, the delivery of gallium ions from these glasses can be improved by altering the calcium ion concentration to control the degradation rate of the glasses. In the present study, the effect of increasing calcium content in novel gallium (Ga2O3)-doped PBGs on the susceptibility of Pseudomonas aeruginosa is examined. The lack of new antibiotics in development makes gallium-doped PBG potentially a highly promising new therapeutic agent. The results show that an increase in calcium content (14, 15 and 16 mol.% CaO) cause a decrease in degradation rate (17.6, 13.5 and 7.3 microg mm(-2) h(-1)), gallium ion release and antimicrobial activity against planktonic P. aeruginosa. The most potent glass composition (containing 14 mol.% CaO) was then evaluated for its ability to prevent the growth of biofilms of P. aeruginosa. Gallium release was found to reduce biofilm growth of P. aeruginosa with a maximum effect (0.86 log(10) CFU reduction compared to Ga2O3-free glasses) after 48 h. Analysis of the biofilms by confocal microscopy confirmed the anti-biofilm effect of these glasses as it showed both viable and non-viable bacteria on the glass surface. Results of the solubility and ion release studies show that this glass system is suitable for controlled delivery of Ga3+. 71Ga NMR and Ga K-edge XANES measurements indicate that the gallium is octahedrally coordinated by oxygen atoms in all samples. The results presented here suggest that PBGs may be useful in controlled drug delivery applications, to deliver gallium ions in order to prevent infections due to P. aeruginosa biofilms.     

Local Ca2+ influx through CRAC channels activates temporally and spatially distinct cellular responses

Ca(2+) entry through store-operated Ca(2+) release-activated Ca(2+) (CRAC) channels controls a disparate array of key cellular responses. In this review, recent work will be described that shows local Ca(2+) influx through CRAC channels has important spatial and temporal consequences on cell function. A localized Ca(2+) rise below the plasma membrane activates, within tens of seconds, catabolic enzymes resulting in the generation of the intracellular messenger arachidonic acid and the paracrine pro-inflammatory molecule LTC(4). In addition, local Ca(2+) entry can activate gene expression, which develops over tens of minutes. Local Ca(2+) influx through CRAC channels therefore has far-reaching consequences on intra- and intercellular communication.